Fianna Fáil TD Jim O’Callaghan is a towering figure. Both in stature and in Fianna Fáil. Although he has been cast to the backbenches of the Dáil in this government, he was once part of the party’s inner circle during the 2016 confidence and supply negotiations and even held a key meeting in his house. He is also tipped to become the new party leader after Taoiseach Mícheál Martin. Despite not being picked for Cabinet, he tells Sam Smyth he still gets on well with Martin and that there was never any falling out between them. He adds that people…